The Bluebook reference sheet gives you (open it from the tools in the top right corner of any Math question):
- Circle: area \(A = \pi r^2\) and circumference \(C = 2\pi r\)
- Rectangle \(A = lw\), triangle \(A = \tfrac{1}{2}bh\), Pythagorean theorem \(c^2 = a^2 + b^2\)
- Special right triangles: 30°-60°-90° (\(x,\ x\sqrt{3},\ 2x\)) and 45°-45°-90° (\(s,\ s,\ s\sqrt{2}\))
- Volumes of a rectangular box, cylinder, sphere, cone and rectangular pyramid
- A circle has 360 degrees and \(2\pi\) radians of arc; the angles of a triangle add up to 180 degrees
Not on the sheet, so memorize: slope and the forms of a line, parallel and perpendicular slopes, the quadratic formula and discriminant, the vertex \(x = -\tfrac{b}{2a}\), exponent rules, exponential growth and decay, percent change, mean, median and probability, the circle equation \((x-h)^2 + (y-k)^2 = r^2\), arc length and sector area, SOH CAH TOA, \(\sin x^\circ = \cos(90^\circ - x^\circ)\), and the distance and midpoint formulas. Jump to the memorize list or see which ones Desmos can replace.
1. The official SAT reference sheet, exactly as Bluebook shows it
College Board's Math directions say it plainly: “Use of a calculator is permitted for all questions. A reference sheet, calculator, and these directions can be accessed throughout the test.” In Bluebook, the tools sit in the top right corner of the screen; in the Math section you see icons for the built-in calculator and the reference sheet there (College Board, 2026-27 Practice Quick Start Guide). You can open the sheet on any of the 44 questions, in both modules.
Here is everything on it. The sheet shows labeled pictures, not names: it never prints the word “sphere” or “cone”, so you need to recognize each figure.
| Figure on the sheet | Formula given | Letters |
|---|---|---|
| Circle | \(A = \pi r^2\) \(C = 2\pi r\) | \(r\) = radius; \(A\) = area; \(C\) = circumference |
| Rectangle | \(A = lw\) | \(l\) = length, \(w\) = width |
| Triangle | \(A = \tfrac{1}{2}bh\) | \(b\) = base, \(h\) = height (perpendicular to the base) |
| Right triangle | \(c^2 = a^2 + b^2\) | \(a, b\) = legs, \(c\) = hypotenuse |
| Special right triangle: 30°-60°-90° | sides \(x,\ x\sqrt{3},\ 2x\) | \(x\) opposite 30°, \(x\sqrt{3}\) opposite 60°, \(2x\) = hypotenuse |
| Special right triangle: 45°-45°-90° | sides \(s,\ s,\ s\sqrt{2}\) | \(s\) = each leg, \(s\sqrt{2}\) = hypotenuse |
| Rectangular box (prism) | \(V = lwh\) | length, width, height |
| Cylinder | \(V = \pi r^2 h\) | \(r\) = radius of the base, \(h\) = height |
| Sphere | \(V = \tfrac{4}{3}\pi r^3\) | \(r\) = radius |
| Cone | \(V = \tfrac{1}{3}\pi r^2 h\) | \(r\) = radius of the base, \(h\) = height |
| Pyramid with a rectangular base | \(V = \tfrac{1}{3}lwh\) | \(l, w\) = base, \(h\) = height |
Below the figures, the sheet prints three facts, word for word:
- “The number of degrees of arc in a circle is 360.”
- “The number of radians of arc in a circle is 2π.”
- “The sum of the measures in degrees of the angles of a triangle is 180.”
Source: College Board, SAT Bluebook Test Directions (Fall 2026), Math Module Directions and Reference Sheet; the same sheet appears in the official SAT Practice Test 9. Tool location: 2026-27 Practice Quick Start Guide.
Three things the sheet gives you without saying so
- Trig values for 30°, 45° and 60°. Combine the special right triangles with SOH CAH TOA: \(\sin 30^\circ = \tfrac{x}{2x} = \tfrac{1}{2}\), \(\cos 30^\circ = \tfrac{\sqrt{3}}{2}\), \(\sin 45^\circ = \cos 45^\circ = \tfrac{1}{\sqrt{2}} = \tfrac{\sqrt{2}}{2}\), \(\tan 60^\circ = \sqrt{3}\).
- The degree-radian conversion. 360 degrees and \(2\pi\) radians describe the same full circle, so \(180^\circ = \pi\) radians. Multiply degrees by \(\tfrac{\pi}{180}\) to get radians.
- Every polygon angle sum. Split an \(n\)-sided polygon into \(n - 2\) triangles from one vertex and use the 180° fact: the interior angles add up to \((n-2) \times 180^\circ\).
What the sheet does not include: surface area formulas, the circle equation, any trig ratios, slope, the quadratic formula or a single statistics formula. That is why Part 2 exists.
The SAT Math section at a glance
| Item | Official detail |
|---|---|
| Questions and time | 44 questions in two modules of 22; 35 minutes per module, 70 minutes in total (about 95 seconds per question) |
| Adaptive modules | Module 1 mixes easy, medium and hard questions; based on how you do, module 2 is more or less difficult. Within each module, questions go from easiest to hardest. |
| Domains | Algebra 13 to 15 questions; Advanced Math 13 to 15; Problem-Solving and Data Analysis 5 to 7; Geometry and Trigonometry 5 to 7 |
| Question formats | About 75% four-option multiple choice; the rest are student-produced responses (SPR), where you type your own answer |
| Word problems | About 30% of Math questions are set in a science, social studies or real-world context |
| Calculator | Built-in Desmos calculator (graphing and scientific) on every Math question, or your own approved handheld calculator without CAS. No calculator in Reading and Writing. |
Sources: College Board, How the SAT Is Structured, The Math Section: Overview, Student-Produced Responses, SAT Suite Calculator Policy.
On the handheld option: College Board bans calculators with CAS (computer algebra system) features, such as the TI-Nspire CX II CAS, TI-89 and HP Prime, and says TI-Nspire models without “CAS” in the name are acceptable. If your own calculator fails during the test, you can keep going on the built-in Desmos. Epic Exam Prep's SAT calculator guide compares the approved handheld models with Desmos if you are deciding which one to use.
- Up to 5 characters for a positive answer, up to 6 for a negative one (the minus sign counts).
- If a fraction does not fit, enter the decimal. If a decimal does not fit, truncate or round at the fourth digit: for \(\tfrac{2}{3}\),
2/3,.6666,.6667,0.666and0.667all get credit, but0.66and0.67do not. - Mixed numbers go in as improper fractions or decimals:
7/2or3.5, never3 1/2or31/2. - No percent signs, commas or currency symbols. If more than one answer is correct, enter just one.
2. SAT math formulas to memorize (not on the reference sheet)
College Board's Assessment Framework for the Digital SAT lists the skills behind every formula below: writing a line from a point and a parallel or perpendicular line, telling when a quadratic has zero, one or two real solutions, the link between a 5% change and a growth factor of 1.05, the circle equation \((x-h)^2 + (y-k)^2 = r^2\), and the relationship between sine and cosine of complementary angles. None of them is on the reference sheet. Each table gives the formula, when the SAT uses it, and a mini example you can check by hand. Every example on this page was verified numerically.
For a domain-by-domain overview of SAT Math and how teachers sequence these topics, read Epic Exam Prep's SAT Math guide.
Algebra (13 to 15 questions)
| Formula | When the SAT uses it | Mini example |
|---|---|---|
| Slope \(m = \dfrac{y_2 - y_1}{x_2 - x_1}\) | Two points, a table of values, or “rate of change” in a word problem. | Through \((2, 5)\) and \((6, 13)\): \(m = \tfrac{13-5}{6-2} = \tfrac{8}{4} = 2\). |
| Forms of a line \(y = mx + b\) \(y - y_1 = m(x - x_1)\) \(Ax + By = C\) | Writing a line from given facts; in standard form the slope is \(-\tfrac{A}{B}\) and the y-intercept is \(\tfrac{C}{B}\). | Slope 2 through \((2, 5)\): \(y - 5 = 2(x - 2)\), so \(y = 2x + 1\). For \(3x + 4y = 12\): slope \(-\tfrac{3}{4}\), y-intercept 3. |
| Parallel and perpendicular parallel: \(m_1 = m_2\) perpendicular: \(m_1 m_2 = -1\) | “Line \(k\) is perpendicular to line \(j\)”, or no-solution systems (parallel lines). | Perpendicular to \(y = \tfrac{2}{3}x + 1\): slope \(-\tfrac{3}{2}\) (flip and change the sign). |
| How many solutions \(a_1x + b_1y = c_1\), \(a_2x + b_2y = c_2\) | Different slopes: one solution. \(\tfrac{a_1}{a_2} = \tfrac{b_1}{b_2} \ne \tfrac{c_1}{c_2}\): no solution. All three ratios equal: infinitely many. Same idea for \(ax + b = cx + d\): \(a = c\) and \(b \ne d\) gives no solution. | \(2x + 3y = 5\) and \(4x + ky = 7\) have no solution when \(k = 6\): \(\tfrac{4}{2} = \tfrac{6}{3} = 2\), but \(\tfrac{7}{5} \ne 2\). |
| Linear model \(f(x) = mx + b\) | Interpreting a model: \(m\) is the change per one unit of \(x\), \(b\) is the value when \(x = 0\). | A tank holds 500 liters and drains 8 liters per minute: \(V = 500 - 8t\). It is empty when \(t = 62.5\) minutes. |
Advanced Math (13 to 15 questions)
| Formula | When the SAT uses it | Mini example |
|---|---|---|
| Quadratic formula \(x = \dfrac{-b \pm \sqrt{b^2 - 4ac}}{2a}\) | Quadratics in standard form that do not factor neatly, or answers with a square root. | \(2x^2 - 3x - 5 = 0\): \(x = \tfrac{3 \pm \sqrt{49}}{4}\), so \(x = \tfrac{5}{2}\) or \(x = -1\). |
| Discriminant \(D = b^2 - 4ac\) | “Exactly one real solution”, “no real solutions”, or a line tangent to a parabola. \(D > 0\): two real solutions; \(D = 0\): one; \(D < 0\): none. | \(x^2 + 6x + k = 0\) has exactly one real solution when \(36 - 4k = 0\), so \(k = 9\). |
| Vertex \(x = -\dfrac{b}{2a}\) \(y = a(x - h)^2 + k\) | Maximum or minimum value, axis of symmetry, or “which form shows the vertex”. In vertex form the vertex is \((h, k)\). | \(y = 2x^2 - 8x + 3\): \(x = \tfrac{8}{4} = 2\), \(y = -5\). Vertex form \(y = 2(x - 2)^2 - 5\); minimum \(-5\). |
| Sum and product of roots \(r_1 + r_2 = -\dfrac{b}{a}\), \(r_1 r_2 = \dfrac{c}{a}\) | “What is the sum of the solutions” when solving would be slow. | \(3x^2 - 12x + 7 = 0\): sum \(= 4\), product \(= \tfrac{7}{3}\). |
| Factoring patterns \(a^2 - b^2 = (a+b)(a-b)\) \((a \pm b)^2 = a^2 \pm 2ab + b^2\) | Equivalent expressions, simplifying rational expressions, spotting a perfect square. | \(49x^2 - 16 = (7x + 4)(7x - 4)\). |
| Exponent rules \(x^a x^b = x^{a+b}\), \(\dfrac{x^a}{x^b} = x^{a-b}\) \((x^a)^b = x^{ab}\), \(x^{-a} = \dfrac{1}{x^a}\) \(x^{m/n} = \sqrt[n]{x^m}\), \(x^0 = 1\) | Rewriting expressions with rational exponents in radical form, and equivalent-expression choices. | \(\dfrac{x^5 \cdot x^{-2}}{x^{1/2}} = x^{5/2} = \sqrt{x^5}\). |
| Exponential growth and decay \(y = a(1 + r)^t\), \(y = a(1 - r)^t\) \(y = a \cdot b^{t/k}\) | Interpreting \(a\) (starting value) and \(b\) (growth factor, \(b > 1\) grows, \(0 < b < 1\) decays). \(b^{t/k}\) means “multiplied by \(b\) every \(k\) units”. | 500 growing 4% a year: \(500(1.04)^t\); after 3 years about 562.43. 1,200 losing 15% a year: \(1200(0.85)^2 = 867\) after 2 years. |
| Graph shifts \(f(x) + k\), \(f(x - h)\), \(-f(x)\) | Matching a transformed graph or equation. \(+k\) moves up \(k\); \(x - h\) moves right \(h\); a minus sign in front reflects over the x-axis. \(f(0)\) is the y-intercept; zeros are x-intercepts. | \(y = (x - 3)^2 + 4\) is \(y = x^2\) moved 3 right and 4 up, so its vertex is \((3, 4)\). |
Problem-Solving and Data Analysis (5 to 7 questions)
| Formula | When the SAT uses it | Mini example |
|---|---|---|
| Percent change \(\dfrac{\text{new} - \text{old}}{\text{old}} \times 100\) growth factor \(1 + \tfrac{p}{100}\) | Increases, decreases, discounts, interest and repeated changes. A 5% increase means multiply by 1.05; a 5% decrease means multiply by 0.95. | 80 to 92: \(\tfrac{12}{80} = 0.15\), a 15% increase. Up 20% then down 20%: \(1.2 \times 0.8 = 0.96\), a 4% net decrease. |
| Rates and unit conversion multiply by factors equal to 1 | Derived units (people per square kilometer, kilowatt-hours) and multistep conversions. | 60 miles per hour \(= \tfrac{60 \times 5280}{3600} = 88\) feet per second. |
| Mean, median, range mean \(= \dfrac{\text{sum}}{n}\) range \(=\) max \(-\) min | Dot plots, histograms, frequency tables, and “what score is needed”. Median is the middle value (the mean of the two middle values when \(n\) is even). An outlier moves the mean far more than the median. | 3, 7, 7, 10, 18: mean 9, median 7, range 15. Average 85 on 4 tests; to average 87 on 5 you need \(5(87) - 4(85) = 95\). |
| Standard deviation (concept) | Comparing spread. Adding the same number to every value leaves the SD unchanged; multiplying every value by \(k\) multiplies the SD by \(|k|\). | \(\{10, 20, 30\}\) and \(\{19, 20, 21\}\) both have mean 20; the first has the larger SD. |
| Probability \(P = \dfrac{\text{favorable}}{\text{total}}\) \(P(A \mid B) = \dfrac{n(A \text{ and } B)}{n(B)}\) | Two-way tables. The “given” group is the denominator. | 48 students play a sport and 18 of them are in grade 12: \(P(\text{grade 12} \mid \text{sport}) = \tfrac{18}{48} = \tfrac{3}{8}\). |
| Margin of error estimate \(\pm\) margin | Which conclusion a sample supports. A larger sample generally gives a smaller margin of error. | 42% with a margin of 3 percentage points: plausible values run from 39% to 45%, so 47% is not supported. |
Geometry and Trigonometry (5 to 7 questions)
| Formula | When the SAT uses it | Mini example |
|---|---|---|
| Circle equation \((x - h)^2 + (y - k)^2 = r^2\) | Center and radius. In expanded form, complete the square: add \(\left(\tfrac{\text{x-coefficient}}{2}\right)^2\) and \(\left(\tfrac{\text{y-coefficient}}{2}\right)^2\) to both sides. | \(x^2 + y^2 + 10x - 4y + 20 = 0\) becomes \((x + 5)^2 + (y - 2)^2 = 9\): center \((-5, 2)\), radius 3. |
| Arc length and sector area arc \(= \dfrac{\theta}{360} \cdot 2\pi r\) sector \(= \dfrac{\theta}{360} \cdot \pi r^2\) | Part of a circle. With \(\theta\) in radians: arc \(= r\theta\), sector \(= \tfrac{1}{2}r^2\theta\). | \(r = 9\), \(\theta = 40^\circ\): arc \(= \tfrac{1}{9} \cdot 18\pi = 2\pi\), sector \(= \tfrac{1}{9} \cdot 81\pi = 9\pi\). |
| Degrees to radians radians \(=\) degrees \(\times \dfrac{\pi}{180}\) | Questions given in radians, unit-circle questions. | \(135^\circ = \tfrac{135\pi}{180} = \tfrac{3\pi}{4}\). |
| SOH CAH TOA \(\sin = \dfrac{\text{opp}}{\text{hyp}}\), \(\cos = \dfrac{\text{adj}}{\text{hyp}}\), \(\tan = \dfrac{\text{opp}}{\text{adj}}\) | Right triangles; similar triangles share the same ratios, so you can find a ratio in the small triangle and use it in the big one. | Right triangle with sides 5, 12, 13 and angle \(A\) opposite 5: \(\sin A = \tfrac{5}{13}\), \(\cos A = \tfrac{12}{13}\), \(\tan A = \tfrac{5}{12}\). |
| Complementary angles \(\sin x^\circ = \cos(90^\circ - x^\circ)\) | “\(\sin a = \cos b\)” with acute angles: the two angles add up to 90°. | \(\sin(2k + 10)^\circ = \cos(3k - 5)^\circ\): \((2k + 10) + (3k - 5) = 90\), so \(k = 17\). |
| Similar figures lengths \(\times k\), areas \(\times k^2\), volumes \(\times k^3\) | Scale drawings, similar triangles, “each side is tripled”. Angles do not change. | Triple every side of a triangle: area \(\times 9\). Double every edge of a cube: volume \(\times 8\). |
| Angle facts polygon sum \((n - 2) \times 180^\circ\) | Vertical angles are equal; a transversal of parallel lines makes equal corresponding and alternate interior angles, and same-side interior angles that add to 180°. | Hexagon: \((6 - 2) \times 180^\circ = 720^\circ\); each angle of a regular hexagon is 120°. |
| Distance and midpoint \(d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}\) \(M = \left(\tfrac{x_1 + x_2}{2}, \tfrac{y_1 + y_2}{2}\right)\) | Radius from a center to a point on a circle; center from the endpoints of a diameter. | \((1, 2)\) and \((7, 10)\): \(d = \sqrt{36 + 64} = 10\), midpoint \((4, 6)\). |
| Pythagorean triples 3-4-5, 5-12-13, 8-15-17, 7-24-25 | Saves the square-root step; multiples work too. | Legs 6 and 8: hypotenuse 10 (the 3-4-5 triple times 2). |
Know the formula, then let Desmos do the arithmetic
SAT Desmos Hacks: The EPIC Method for Smart, Fast, 800-Level Math (Revised and Expanded Edition, October 2026) has 100 Digital SAT math problems across all four domains, 27 Desmos power moves, and an honest label on every problem: Desmos is faster, algebra first, or algebra only. 334 full-color pages. All 100 problems are free to practice at desmos.prepdrills.com with the book.
3. Or let Desmos do it: one line instead of the formula
Desmos is built into Bluebook for the whole Math section, and for many formulas in Part 2 it gets you the number faster than the algebra. The table below uses the same syntax as our Desmos SAT cheat sheet: type ^ for powers, _ for subscripts and ~ for regressions. The last column is the honest verdict, because opening Desmos for a 5-second calculation costs time.
| Instead of | Type in Desmos | What to read | Faster? |
|---|---|---|---|
| Quadratic formula | y = 2x^2 - 3x - 5 | Grey dots on the x-axis: \(x = -1\) and \(x = 2.5\) | Desmos |
| Vertex formula, completing the square | y = 2x^2 - 8x + 3 | Grey dot at the turning point: \((2, -5)\) | Desmos |
| Discriminant with a constant | y = x^2 + 6x + k, then “add slider” for k | The k at which the parabola just touches the x-axis: \(k = 9\) | Desmos for numbers; algebra if the answer is in terms of a variable |
| Solving a system, number of solutions | Equation 1 on line 1, equation 2 on line 2, exactly as written | Intersection point; parallel lines mean no solution, one line on top of the other means infinitely many | Desmos |
| Circle equation (completing the square twice) | x^2 + y^2 + 10x - 4y + 20 = 0, then midpoint((-5, 5), (-5, -1)) | Click the top and bottom points; the midpoint \((-5, 2)\) is the center and half the distance between them, 3, is the radius | Desmos |
| Exponent rules, factoring patterns | Original expression on line 1, each answer choice on its own line | The choice whose graph sits exactly on top of line 1 | Desmos when the algebra is messy |
| Building an exponential or linear model from data | Add a table, then y_1 ~ ab^{x_1} or y_1 ~ mx_1 + b | The values of a and b (or m and b) | Desmos |
| Mean, median, standard deviation | L = [3, 7, 7, 10, 18], then mean(L), median(L), stdev(L) | 9, 7 and the spread; stdev is the sample version, stdevp the population one | Desmos for long lists |
| Distance formula | distance((1, 2), (7, 10)) | 10 | Either |
| Growth, percent and arc arithmetic | 500(1.04)^3, (92 - 80)/80, 40/360*2pi*9 | 562.432, 0.15, 6.283 (that is \(2\pi\): divide by pi if the choices are in terms of \(\pi\)) | Desmos for the arithmetic only; you still need the formula |
| Sum or product of roots, complementary angles | Not worth it | \(-\tfrac{b}{a}\), \(\tfrac{c}{a}\), or set the two angles to add up to 90 | By hand |
What Desmos cannot replace: choosing the formula. For arc length, sector area, SOH CAH TOA, similar figures, probability and margin of error, Desmos only does the arithmetic once you know what to compute. For trig values, check whether the calculator is set to degrees or radians before you type sin(40); in radian mode, type sin(40pi/180) for \(\sin 40^\circ\). For the full method, with when to skip Desmos, read how to use Desmos on the Digital SAT.
How to learn these formulas before test day
- Learn the sheet's layout, not its formulas. You will look things up on test day, so know where each figure sits. Spend your memory on Part 2.
- Prioritize by question count. Algebra and Advanced Math make up 26 to 30 of the 44 questions. Slope, the forms of a line, the solution-count rules, the discriminant, the vertex and exponential models pay off most.
- Pair every formula with its Desmos move. Solve each mini example above by hand, then check it in Desmos. When both routes feel automatic, you can choose the faster one in a second.
- Test it under time. Take a full-length practice test in Bluebook and convert your result with our Digital SAT score calculator. If a term on your score report is unfamiliar, the SAT glossary defines it.
Preparing for the other section too? Our SAT Words in Context guide covers the most common Reading and Writing question type, and SAT test dates 2026-2027 for international students helps you pick a date that leaves time to learn this list.
Want every formula applied to real SAT-style problems?
SAT Desmos Hacks takes the formulas on this page and shows, problem by problem, when Desmos beats them and when it does not. The Revised and Expanded Edition (published October 22, 2026; ISBN 979-8164363543) has 100 problems from Easy to Hard across all four Math domains, 27 Desmos power moves, the trap answer and the by-hand route for every question, and every Desmos step tested in the Bluebook version of Desmos.
SAT Desmos Hacks: The EPIC Method for Smart, Fast, 800-Level Math
Revised and Expanded Edition (2026) · By Jaclyn Caruana, MBA · 334 full-color pages · 100 problems · 27 Desmos power moves · Free interactive practice for all 100 problems at desmos.prepdrills.com. Kindle and paperback on Amazon.
SAT is a registered trademark of the College Board, which is not affiliated with and does not endorse this page or book.
Frequently asked questions
What formulas are on the Digital SAT reference sheet?
The Bluebook reference sheet gives the area and circumference of a circle (A = πr², C = 2πr), the area of a rectangle (A = lw) and of a triangle (A = ½bh), the Pythagorean theorem (c² = a² + b²), the 30°-60°-90° and 45°-45°-90° special right triangles, and the volumes of a rectangular box (V = lwh), a cylinder (V = πr²h), a sphere (V = 4/3 πr³), a cone (V = 1/3 πr²h) and a rectangular pyramid (V = 1/3 lwh). It also states that a circle has 360 degrees and 2π radians of arc and that the angles of a triangle add up to 180 degrees.
Where is the formula sheet on the Digital SAT?
In the Math section of Bluebook, the reference sheet is one of the tools in the top right corner of the screen, next to the built-in Desmos calculator. College Board's Math directions say the reference sheet, calculator and directions can be accessed throughout the test, so you can open it on any of the 44 Math questions in either module.
Which SAT math formulas are not on the reference sheet?
Slope, the forms of a line, parallel and perpendicular slopes, the quadratic formula, the discriminant, the vertex formula x = -b/(2a), exponent rules, exponential growth and decay, percent change, mean, median and range, probability, the circle equation (x - h)² + (y - k)² = r², arc length and sector area, SOH CAH TOA, sin x° = cos(90° - x°), and the distance and midpoint formulas. College Board's Assessment Framework lists skills that use all of these, so learn them before test day.
Is the quadratic formula on the SAT reference sheet?
No. The quadratic formula, x = (-b ± √(b² - 4ac)) / (2a), is not on the sheet, and neither is the discriminant b² - 4ac. You can often skip both by graphing the quadratic in Desmos and clicking the x-intercepts, but questions with an unknown constant or an answer in terms of a variable still need the algebra.
Do you need to memorize formulas if you have Desmos on the SAT?
Yes, but fewer of them. Desmos can replace the quadratic formula, the vertex formula, completing the square for circles and statistics arithmetic on many questions. It does not tell you which formula a geometry, trigonometry, percent or probability question needs, and it cannot give an answer in terms of a variable. Memorize the short list on this page and use Desmos to check.
How many questions are in the SAT Math section and how long is it?
The Math section has 44 questions in two modules of 22 questions, with 35 minutes per module (70 minutes in total). About 75% of the questions are multiple choice and the rest are student-produced responses, where you type your own answer. You can use the built-in Desmos calculator, or an approved handheld calculator without CAS features, on every Math question.
How do you enter fractions and decimals on SAT student-produced response questions?
You can enter up to 5 characters for a positive answer and up to 6 for a negative one. If a fraction does not fit, enter its decimal; if a decimal does not fit, truncate or round at the fourth digit, so 2/3 can be entered as 2/3, .6666 or .6667 but not 0.67. Enter mixed numbers as improper fractions or decimals (7/2 or 3.5, not 3 1/2), and do not type percent signs or commas.
Can I print this SAT math formula sheet?
Yes. Use the Print this formula sheet button or your browser's print command (Ctrl+P, or Cmd+P on a Mac) and choose Save as PDF to keep a copy. The printout keeps the official reference sheet, the formulas to memorize and the Desmos table, and leaves out menus and promotions. On test day you use the official reference sheet built into Bluebook.